[Issued in loose-leaf form for use of the service. This chapter has also been issued for sale in pamphlet form with title, Instructions for operation and maintenance of measuring instruments, for which see Monthly catalog for July 1941, p. 1068.]
Notes:
[Issued in loose-leaf form for use of the service. This chapter has also been issued for sale in pamphlet form with title, Instructions for operation and maintenance of measuring instruments, for which see Monthly catalog for July 1941, p. 1068.] ‡ Official Use. Not Available.